Dengue fever. It causes pain, nausea, and can be deadly. Worst of all, there's no known cure or vaccine. Which is why 6,000 genetically modified mosquitoes are being deployed in Malaysia to kill of dengue at the root.

Dengue gets passed around by the female Aedes aegypti mosquito, commonly found in Southeast Asia. The 6,000 mosquitoes in question are all males, scientifically engineered to have shorter lifespans—meaning they won't be around long enough to do much damage. By driving down the mosquito population, scientists hope to curb Dengue fever if not eliminate it entirely.

All of which has lead to some ethical concerns among locals and outside observers. Can we really fuss with the gene pool of a species so brazenly? And while adding 6,000 mosquitoes to the mix may help stem Dengue fever, it also, uh, adds a lot of mosquitoes to a place that's already riddled with the pests. Still, I'd rather a quick bite from a harmless bug than a horrible, life-threatening disease. [AFPFast Company]